class Baz implements EntityInterface
{
    /** @var Foo[]|Collection */
    private $foo;

    /** @var Bar */
    private $bar;

    private function __construct()
    {
        $this->foo = new Collection();
    }

    /**
     * {@inheritdoc}
     *
     * @return self
     *
     * @throws Exception
     */
    public static function fromState(array $state): EntityInterface
    {
        $baz = new self();

        foreach ($state as $property => $value) {
            switch ($property) {
                case 'bar':
                    if ($value instanceof Bar) {
                        $baz->bar = $value;
                    }

                    break;
                case 'foo':
                    if ($value instanceof Collection) {
                        $baz->foo = $value;
                    }

                    break;
            }
        }

        return $baz;
    }

    public function getBar(): ?Bar
    {
        return $this->bar;
    }

    /**
     * @return Foo[]
     */
    public function getFoo(): array
    {
        return $this->foo->toArray();
    }
}

abstract class AbstractDataMapper
{
    /* @var AbstactEntityFactory */
    protected $factory;

    public function __construct(AbstactEntityFactory $factory)
    {
        $this->factory = $factory;
    }

    /**
     * @param mixed[] $state
     */
    public function map(array $state): EntityInterface
    {
        return $this->factory->create($state);
    }
}


class BazMapper extends AbstractDataMapper
{
    /* @var AbstactEntityFactory[] */
    protected $factories;

    /**
     * @param AbstactEntityFactory[] $factories
     */
    public function __construct(BazFactory $factory, array $factories)
    {
        parent::__construct($factory);

        $this->factories = $factories;
    }

    /**
     * {@inheritdoc}
     *
     * @return Baz
     */
    public function map(array $state): EntityInterface
    {
        foreach ($this->factories as $factory) {
            $state[$factory->getName()] = $factory->get(self::getFieldsWithValues($factory, $state));
        }

        return $this->factory->create($state);
    }
}

new BazMapper(
    new BazFactory(),
    [
        new BarFactory(),
        new FooFactory(),
    ]
);